crypto: gf128mul - remove dead gf128mul_64k_lle code

This code is unlikely to be useful in the future because transforms
don't know how often keys will be changed, new algorithms are unlikely
to use lle representation, and tables should be replaced with
carryless multiplication instructions when available.

Signed-off-by: Alex Cope <alexcope@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>